├── .gitignore ├── LICENSE ├── README.md ├── pom.xml └── src ├── main ├── java │ └── com │ │ └── redis │ │ └── lock │ │ ├── LockApplication.java │ │ ├── annotation │ │ └── RedisLock.java │ │ ├── aop │ │ └── LockMethodAspect.java │ │ ├── config │ │ └── RedisProperties.java │ │ ├── controller │ │ └── TestController.java │ │ └── utils │ │ ├── JedisUtil.java │ │ ├── RedisLockHelper.java │ │ └── RedissonUtils.java └── resources │ └── application.properties └── test └── java └── com └── redis └── lock ├── LockApplicationTests.java └── RedisLockTest.java /.gitignore: -------------------------------------------------------------------------------- 1 | /target/ 2 | !.mvn/wrapper/maven-wrapper.jar 3 | target 4 | 5 | 6 | ### IntelliJ IDEA ### 7 | .idea 8 | *.iws 9 | *.iml 10 | *.ipr 11 | .mvn 12 | mvnw.cmd 13 | mvnw 14 | redis-distributed-lock.iml 15 | 16 | 17 | 18 | -------------------------------------------------------------------------------- /LICENSE: -------------------------------------------------------------------------------- 1 | Apache License 2 | Version 2.0, January 2004 3 | http://www.apache.org/licenses/ 4 | 5 | TERMS AND CONDITIONS FOR USE, REPRODUCTION, AND DISTRIBUTION 6 | 7 | 1. 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Redlock算法 与 Redisson 实现 110 | 111 | Redis作者 antirez基于分布式环境下提出了一种更高级的分布式锁的实现Redlock，原理如下： 112 | 113 | 114 | > 下面参考文章[Redlock：Redis分布式锁最牛逼的实现](https://mp.weixin.qq.com/s?__biz=MzU5ODUwNzY1Nw==&mid=2247484155&idx=1&sn=0c73f45f2f641ba0bf4399f57170ac9b&scene=21#wechat_redirect) 和 https://redis.io/topics/distlock 115 | 116 | 117 | 假设有5个独立的Redis节点（**注意这里的节点可以是5个Redis单master实例，也可以是5个Redis Cluster集群，但并不是有5个主节点的cluster集群**）： 118 | 119 | - 获取当前Unix时间，以毫秒为单位 120 | - 依次尝试从5个实例，使用相同的key和具有唯一性的value(例如UUID)获取锁，当向Redis请求获取锁时，客户端应该设置一个网络连接和响应超时时间，这个超时时间应用小于锁的失效时间，例如你的锁自动失效时间为10s，则超时时间应该在5~50毫秒之间，这样可以避免服务器端Redis已经挂掉的情况下，客户端还在死死地等待响应结果。如果服务端没有在规定时间内响应，客户端应该尽快尝试去另外一个Redis实例请求获取锁 121 | - 客户端使用当前时间减去开始获取锁时间（步骤1记录的时间）就得到获取锁使用的时间，当且仅当从大多数(N/2+1，这里是3个节点)的Redis节点都取到锁，并且使用的时间小于锁失败时间时，锁才算获取成功。 122 | - 如果取到了锁，key的真正有效时间等于有效时间减去获取锁所使用的时间（步骤3计算的结果） 123 | - 如果某些原因，获取锁失败（没有在至少N/2+1个Redis实例取到锁或者取锁时间已经超过了有效时间），客户端应该在所有的Redis实例上进行解锁（即便某些Redis实例根本就没有加锁成功，防止某些节点获取到锁但是客户端没有得到响应而导致接下来的一段时间不能被重新获取锁） 124 | 125 | #### Redisson实现简单分布式锁 126 | 127 | 对于Java用户而言，我们经常使用Jedis，Jedis是Redis的Java客户端，除了Jedis之外，Redisson也是Java的客户端，Jedis是阻塞式I/O，而Redisson底层使用Netty可以实现非阻塞I/O，该客户端封装了锁的，继承了J.U.C的Lock接口，所以我们可以像使用ReentrantLock一样使用Redisson，具体使用过程如下。 128 | 129 | 1. 首先加入POM依赖 130 | 131 | ```xml 132 | 133 | org.redisson 134 | redisson 135 | 3.10.6 136 | 137 | ``` 138 | 2. 使用Redisson，代码如下(与使用ReentrantLock类似） 139 | 140 | 141 | ```java 142 | // 1. 配置文件 143 | Config config = new Config(); 144 | config.useSingleServer() 145 | .setAddress("redis://127.0.0.1:6379") 146 | .setPassword(RedisConfig.PASSWORD) 147 | .setDatabase(0); 148 | //2. 构造RedissonClient 149 | RedissonClient redissonClient = Redisson.create(config); 150 | 151 | //3. 设置锁定资源名称 152 | RLock lock = redissonClient.getLock("redlock"); 153 | lock.lock(); 154 | try { 155 | System.out.println("获取锁成功，实现业务逻辑"); 156 | Thread.sleep(10000); 157 | } catch (InterruptedException e) { 158 | e.printStackTrace(); 159 | } finally { 160 | lock.unlock(); 161 | } 162 | ``` 163 | 关于Redlock算法的实现，在Redisson中我们可以使用RedissonRedLock来完成，具体使用细节可以参考大佬的文章： https://mp.weixin.qq.com/s/8uhYult2h_YUHT7q7YCKYQ 164 | 165 | ## Redis实现的分布式锁轮子 166 | 167 | 下面利用SpringBoot + Jedis + AOP的组合来实现一个简易的分布式锁。 168 | 169 | 170 | 171 | ### 1. 自定义注解 172 | 自定义一个注解，被注解的方法会执行获取分布式锁的逻辑 173 | ```java 174 | @Target(ElementType.METHOD) 175 | @Retention(RetentionPolicy.RUNTIME) 176 | @Documented 177 | @Inherited 178 | public @interface RedisLock { 179 | /** 180 | * 业务键 181 | * 182 | * @return 183 | */ 184 | String key(); 185 | /** 186 | * 锁的过期秒数,默认是5秒 187 | * 188 | * @return 189 | */ 190 | int expire() default 5; 191 | 192 | /** 193 | * 尝试加锁，最多等待时间 194 | * 195 | * @return 196 | */ 197 | long waitTime() default Long.MIN_VALUE; 198 | /** 199 | * 锁的超时时间单位 200 | * 201 | * @return 202 | */ 203 | TimeUnit timeUnit() default TimeUnit.SECONDS; 204 | } 205 | ``` 206 | ### 2. AOP拦截器实现 207 | 在AOP中我们去执行获取分布式锁和释放分布式锁的逻辑，代码如下： 208 | ```java 209 | @Aspect 210 | @Component 211 | public class LockMethodAspect { 212 | @Autowired 213 | private RedisLockHelper redisLockHelper; 214 | @Autowired 215 | private JedisUtil jedisUtil; 216 | private Logger logger = LoggerFactory.getLogger(LockMethodAspect.class); 217 | 218 | @Around("@annotation(com.redis.lock.annotation.RedisLock)") 219 | public Object around(ProceedingJoinPoint joinPoint) { 220 | Jedis jedis = jedisUtil.getJedis(); 221 | MethodSignature signature = (MethodSignature) joinPoint.getSignature(); 222 | Method method = signature.getMethod(); 223 | 224 | RedisLock redisLock = method.getAnnotation(RedisLock.class); 225 | String value = UUID.randomUUID().toString(); 226 | String key = redisLock.key(); 227 | try { 228 | final boolean islock = redisLockHelper.lock(jedis,key, value, redisLock.expire(), redisLock.timeUnit()); 229 | logger.info("isLock : {}",islock); 230 | if (!islock) { 231 | logger.error("获取锁失败"); 232 | throw new RuntimeException("获取锁失败"); 233 | } 234 | try { 235 | return joinPoint.proceed(); 236 | } catch (Throwable throwable) { 237 | throw new RuntimeException("系统异常"); 238 | } 239 | } finally { 240 | logger.info("释放锁"); 241 | redisLockHelper.unlock(jedis,key, value); 242 | jedis.close(); 243 | } 244 | } 245 | } 246 | 247 | ``` 248 | ### 3. Redis实现分布式锁核心类 249 | ```java 250 | @Component 251 | public class RedisLockHelper { 252 | private long sleepTime = 100; 253 | /** 254 | * 直接使用setnx + expire方式获取分布式锁 255 | * 非原子性 256 | * 257 | * @param key 258 | * @param value 259 | * @param timeout 260 | * @return 261 | */ 262 | public boolean lock_setnx(Jedis jedis,String key, String value, int timeout) { 263 | Long result = jedis.setnx(key, value); 264 | // result = 1时，设置成功，否则设置失败 265 | if (result == 1L) { 266 | return jedis.expire(key, timeout) == 1L; 267 | } else { 268 | return false; 269 | } 270 | } 271 | 272 | /** 273 | * 使用Lua脚本，脚本中使用setnex+expire命令进行加锁操作 274 | * 275 | * @param jedis 276 | * @param key 277 | * @param UniqueId 278 | * @param seconds 279 | * @return 280 | */ 281 | public boolean Lock_with_lua(Jedis jedis,String key, String UniqueId, int seconds) { 282 | String lua_scripts = "if redis.call('setnx',KEYS[1],ARGV[1]) == 1 then" + 283 | "redis.call('expire',KEYS[1],ARGV[2]) return 1 else return 0 end"; 284 | List keys = new ArrayList<>(); 285 | List values = new ArrayList<>(); 286 | keys.add(key); 287 | values.add(UniqueId); 288 | values.add(String.valueOf(seconds)); 289 | Object result = jedis.eval(lua_scripts, keys, values); 290 | //判断是否成功 291 | return result.equals(1L); 292 | } 293 | 294 | /** 295 | * 在Redis的2.6.12及以后中,使用 set key value [NX] [EX] 命令 296 | * 297 | * @param key 298 | * @param value 299 | * @param timeout 300 | * @return 301 | */ 302 | public boolean lock(Jedis jedis,String key, String value, int timeout, TimeUnit timeUnit) { 303 | long seconds = timeUnit.toSeconds(timeout); 304 | return "OK".equals(jedis.set(key, value, "NX", "EX", seconds)); 305 | } 306 | 307 | /** 308 | * 自定义获取锁的超时时间 309 | * 310 | * @param jedis 311 | * @param key 312 | * @param value 313 | * @param timeout 314 | * @param waitTime 315 | * @param timeUnit 316 | * @return 317 | * @throws InterruptedException 318 | */ 319 | public boolean lock_with_waitTime(Jedis jedis,String key, String value, int timeout, long waitTime,TimeUnit timeUnit) throws InterruptedException { 320 | long seconds = timeUnit.toSeconds(timeout); 321 | while (waitTime >= 0) { 322 | String result = jedis.set(key, value, "nx", "ex", seconds); 323 | if ("OK".equals(result)) { 324 | return true; 325 | } 326 | waitTime -= sleepTime; 327 | Thread.sleep(sleepTime); 328 | } 329 | return false; 330 | } 331 | /** 332 | * 错误的解锁方法—直接删除key 333 | * 334 | * @param key 335 | */ 336 | public void unlock_with_del(Jedis jedis,String key) { 337 | jedis.del(key); 338 | } 339 | 340 | /** 341 | * 使用Lua脚本进行解锁操纵，解锁的时候验证value值 342 | * 343 | * @param jedis 344 | * @param key 345 | * @param value 346 | * @return 347 | */ 348 | public boolean unlock(Jedis jedis,String key,String value) { 349 | String luaScript = "if redis.call('get',KEYS[1]) == ARGV[1] then " + 350 | "return redis.call('del',KEYS[1]) else return 0 end"; 351 | return jedis.eval(luaScript, Collections.singletonList(key), Collections.singletonList(value)).equals(1L); 352 | } 353 | } 354 | ``` 355 | 356 | ### 4. Controller层控制 357 | 定义一个TestController来测试我们实现的分布式锁 358 | ```java 359 | @RestController 360 | public class TestController { 361 | @RedisLock(key = "redis_lock") 362 | @GetMapping("/index") 363 | public String index() { 364 | return "index"; 365 | } 366 | } 367 | ``` 368 | 369 | ## 小结 370 | 分布式锁重点在于互斥性，在任意一个时刻，只有一个客户端获取了锁。在实际的生产环境中，分布式锁的实现可能会更复杂，而我这里的讲述主要针对的是单机环境下的基于Redis的分布式锁实现，至于Redis集群环境并没有过多涉及，有兴趣的朋友可以查阅相关资料。 371 | 372 | ## 参考资料 & 鸣谢 373 | 374 | - https://mp.weixin.qq.com/s/eHsuEc8Dq3h1Kz1uqBWsjA 375 | - https://mp.weixin.qq.com/s/y2HPj2ji2KLS_eTR5nBnDA 376 | - https://mp.weixin.qq.com/s/8uhYult2h_YUHT7q7YCKYQ 377 | - https://mp.weixin.qq.com/s/xCe2ljuhMWD2rsstmNab_Q 378 | - https://crossoverjie.top/2018/03/29/distributed-lock/distributed-lock-redis/ 379 | - https://blog.battcn.com/2018/06/13/springboot/v2-cache-redislock/#%E5%85%B7%E4%BD%93%E4%BB%A3%E7%A0%81 380 | - https://redis.io/topics/distlock 381 | -------------------------------------------------------------------------------- /pom.xml: -------------------------------------------------------------------------------- 1 | 2 | 4 | 4.0.0 5 | 6 | org.springframework.boot 7 | spring-boot-starter-parent 8 | 2.1.4.RELEASE 9 | 10 | 11 | com.redis 12 | lock 13 | 0.0.1-SNAPSHOT 14 | lock 15 | Demo project for Spring Boot 16 | 17 | 18 | 1.8 19 | 20 | 21 | 22 | 23 | org.springframework.boot 24 | spring-boot-starter 25 | 26 | 27 | org.springframework.boot 28 | spring-boot-starter-web 29 | 30 | 31 | redis.clients 32 | jedis 33 | 34 | 35 | org.redisson 36 | redisson 37 | 3.10.6 38 | 39 | 40 | org.springframework.boot 41 | spring-boot-starter-aop 42 | 43 | 44 | org.projectlombok 45 | lombok 46 | true 47 | 48 | 49 | org.springframework.boot 50 | spring-boot-starter-test 51 | test 52 | 53 | 54 | 55 | 56 | 57 | 58 | org.springframework.boot 59 | spring-boot-maven-plugin 60 | 61 | 62 | 63 | 64 | 65 | -------------------------------------------------------------------------------- /src/main/java/com/redis/lock/LockApplication.java: -------------------------------------------------------------------------------- 1 | package com.redis.lock; 2 | 3 | import org.springframework.boot.SpringApplication; 4 | import org.springframework.boot.autoconfigure.SpringBootApplication; 5 | 6 | @SpringBootApplication 7 | public class LockApplication { 8 | 9 | public static void main(String[] args) { 10 | SpringApplication.run(LockApplication.class, args); 11 | } 12 | 13 | } 14 | -------------------------------------------------------------------------------- /src/main/java/com/redis/lock/annotation/RedisLock.java: -------------------------------------------------------------------------------- 1 | package com.redis.lock.annotation; 2 | 3 | import java.lang.annotation.*; 4 | import java.util.concurrent.TimeUnit; 5 | 6 | @Target(ElementType.METHOD) 7 | @Retention(RetentionPolicy.RUNTIME) 8 | @Documented 9 | @Inherited 10 | public @interface RedisLock { 11 | /** 12 | * 业务键 13 | * 14 | * @return 15 | */ 16 | String key(); 17 | /** 18 | * 锁的过期秒数,默认是5秒 19 | * 20 | * @return 21 | */ 22 | int expire() default 5; 23 | 24 | /** 25 | * 尝试加锁，最多等待时间 26 | * 27 | * @return 28 | */ 29 | long waitTime() default Long.MIN_VALUE; 30 | /** 31 | * 锁的超时时间单位 32 | * 33 | * @return 34 | */ 35 | TimeUnit timeUnit() default TimeUnit.SECONDS; 36 | } 37 | -------------------------------------------------------------------------------- /src/main/java/com/redis/lock/aop/LockMethodAspect.java: -------------------------------------------------------------------------------- 1 | package com.redis.lock.aop; 2 | 3 | import com.redis.lock.annotation.RedisLock; 4 | import com.redis.lock.utils.JedisUtil; 5 | import com.redis.lock.utils.RedisLockHelper; 6 | import lombok.extern.slf4j.Slf4j; 7 | import org.aspectj.lang.ProceedingJoinPoint; 8 | import org.aspectj.lang.annotation.Around; 9 | import org.aspectj.lang.annotation.Aspect; 10 | import org.aspectj.lang.reflect.MethodSignature; 11 | import org.slf4j.Logger; 12 | import org.slf4j.LoggerFactory; 13 | import org.springframework.beans.factory.annotation.Autowired; 14 | import org.springframework.stereotype.Component; 15 | import redis.clients.jedis.Jedis; 16 | 17 | import java.lang.reflect.Method; 18 | import java.util.UUID; 19 | 20 | /** 21 | * @description: AOP拦截器 22 | * @author: pjmike 23 | * @create: 2019/04/24 18:43 24 | */ 25 | @Aspect 26 | @Component 27 | public class LockMethodAspect { 28 | @Autowired 29 | private RedisLockHelper redisLockHelper; 30 | @Autowired 31 | private JedisUtil jedisUtil; 32 | private Logger logger = LoggerFactory.getLogger(LockMethodAspect.class); 33 | 34 | @Around("@annotation(com.redis.lock.annotation.RedisLock)") 35 | public Object around(ProceedingJoinPoint joinPoint) { 36 | Jedis jedis = jedisUtil.getJedis(); 37 | MethodSignature signature = (MethodSignature) joinPoint.getSignature(); 38 | Method method = signature.getMethod(); 39 | 40 | RedisLock redisLock = method.getAnnotation(RedisLock.class); 41 | String value = UUID.randomUUID().toString(); 42 | String key = redisLock.key(); 43 | try { 44 | final boolean islock = redisLockHelper.lock(jedis,key, value, redisLock.expire(), redisLock.timeUnit()); 45 | logger.info("isLock : {}",islock); 46 | if (!islock) { 47 | logger.error("获取锁失败"); 48 | throw new RuntimeException("获取锁失败"); 49 | } 50 | try { 51 | return joinPoint.proceed(); 52 | } catch (Throwable throwable) { 53 | throw new RuntimeException("系统异常"); 54 | } 55 | } finally { 56 | logger.info("释放锁"); 57 | redisLockHelper.unlock(jedis,key, value); 58 | jedis.close(); 59 | } 60 | } 61 | } 62 | -------------------------------------------------------------------------------- /src/main/java/com/redis/lock/config/RedisProperties.java: -------------------------------------------------------------------------------- 1 | package com.redis.lock.config; 2 | 3 | import org.springframework.boot.context.properties.ConfigurationProperties; 4 | import org.springframework.stereotype.Component; 5 | 6 | /** 7 | * @description: 8 | * @author: pjmike 9 | * @create: 2019/04/24 19:01 10 | */ 11 | @Component 12 | @ConfigurationProperties(prefix = "redis.config") 13 | public class RedisProperties { 14 | private int max_idle; 15 | private int max_wait; 16 | private String host; 17 | private int port; 18 | private String password; 19 | private int retry_num; 20 | private int timeout; 21 | 22 | public int getMax_idle() { 23 | return max_idle; 24 | } 25 | 26 | public void setMax_idle(int max_idle) { 27 | this.max_idle = max_idle; 28 | } 29 | 30 | public int getMax_wait() { 31 | return max_wait; 32 | } 33 | 34 | public void setMax_wait(int max_wait) { 35 | this.max_wait = max_wait; 36 | } 37 | 38 | public String getHost() { 39 | return host; 40 | } 41 | 42 | public void setHost(String host) { 43 | this.host = host; 44 | } 45 | 46 | public int getPort() { 47 | return port; 48 | } 49 | 50 | public void setPort(int port) { 51 | this.port = port; 52 | } 53 | 54 | public String getPassword() { 55 | return password; 56 | } 57 | 58 | public void setPassword(String password) { 59 | this.password = password; 60 | } 61 | 62 | public int getRetry_num() { 63 | return retry_num; 64 | } 65 | 66 | public void setRetry_num(int retry_num) { 67 | this.retry_num = retry_num; 68 | } 69 | 70 | public int getTimeout() { 71 | return timeout; 72 | } 73 | 74 | public void setTimeout(int timeout) { 75 | this.timeout = timeout; 76 | } 77 | } 78 | -------------------------------------------------------------------------------- /src/main/java/com/redis/lock/controller/TestController.java: -------------------------------------------------------------------------------- 1 | package com.redis.lock.controller; 2 | 3 | import com.redis.lock.annotation.RedisLock; 4 | import org.springframework.web.bind.annotation.GetMapping; 5 | import org.springframework.web.bind.annotation.RestController; 6 | 7 | /** 8 | * @description: 9 | * @author: pjmike 10 | * @create: 2019/04/24 21:30 11 | */ 12 | @RestController 13 | public class TestController { 14 | @RedisLock(key = "redis_lock") 15 | @GetMapping("/index") 16 | public String index() { 17 | return "index"; 18 | } 19 | } 20 | -------------------------------------------------------------------------------- /src/main/java/com/redis/lock/utils/JedisUtil.java: -------------------------------------------------------------------------------- 1 | package com.redis.lock.utils; 2 | 3 | 4 | import com.redis.lock.config.RedisProperties; 5 | import org.slf4j.Logger; 6 | import org.slf4j.LoggerFactory; 7 | import org.springframework.beans.factory.annotation.Autowired; 8 | import org.springframework.stereotype.Component; 9 | import redis.clients.jedis.Jedis; 10 | import redis.clients.jedis.JedisPool; 11 | import redis.clients.jedis.JedisPoolConfig; 12 | 13 | import java.util.Map; 14 | import java.util.concurrent.ConcurrentHashMap; 15 | 16 | /** 17 | * @description: 18 | * @author: pjmike 19 | * @create: 2019/04/23 19:29 20 | */ 21 | @Component 22 | public class JedisUtil { 23 | @Autowired 24 | private RedisProperties redisProperties; 25 | private Logger logger = LoggerFactory.getLogger(JedisUtil.class); 26 | 27 | private Map map = new ConcurrentHashMap<>(); 28 | 29 | private JedisPool getPool() { 30 | String key = redisProperties.getHost() + ":" + redisProperties.getHost(); 31 | JedisPool pool; 32 | if (!map.containsKey(key)) { 33 | JedisPoolConfig config = new JedisPoolConfig(); 34 | config.setMaxIdle(redisProperties.getMax_idle()); 35 | config.setMaxWaitMillis(redisProperties.getMax_wait()); 36 | config.setTestOnBorrow(true); 37 | config.setTestOnReturn(true); 38 | 39 | pool = new JedisPool(config,redisProperties.getHost(),redisProperties.getPort(),redisProperties.getTimeout(),redisProperties.getPassword()); 40 | map.put(key, pool); 41 | } else { 42 | pool = map.get(key); 43 | } 44 | return pool; 45 | } 46 | 47 | public Jedis getJedis() { 48 | Jedis jedis = null; 49 | int count = 0; 50 | do { 51 | try { 52 | jedis = getPool().getResource(); 53 | count++; 54 | } catch (Exception e) { 55 | logger.error("get jedis failed ", e); 56 | if (jedis != null) { 57 | jedis.close(); 58 | } 59 | } 60 | } while (jedis == null && count < redisProperties.getRetry_num()); 61 | return jedis; 62 | } 63 | } 64 | -------------------------------------------------------------------------------- /src/main/java/com/redis/lock/utils/RedisLockHelper.java: -------------------------------------------------------------------------------- 1 | package com.redis.lock.utils; 2 | import org.springframework.stereotype.Component; 3 | import redis.clients.jedis.Jedis; 4 | 5 | import java.util.ArrayList; 6 | import java.util.Collections; 7 | import java.util.List; 8 | import java.util.concurrent.TimeUnit; 9 | 10 | /** 11 | * @description: Redis实现分布式锁 12 | * @author: pjmike 13 | * @create: 2019/04/23 19:52 14 | */ 15 | @Component 16 | public class RedisLockHelper { 17 | private long sleepTime = 100; 18 | /** 19 | * 直接使用setnx + expire方式获取分布式锁 20 | * 非原子性 21 | * 22 | * @param key 23 | * @param value 24 | * @param timeout 25 | * @return 26 | */ 27 | public boolean lock_setnx(Jedis jedis,String key, String value, int timeout) { 28 | Long result = jedis.setnx(key, value); 29 | // result = 1时，设置成功，否则设置失败 30 | if (result == 1L) { 31 | return jedis.expire(key, timeout) == 1L; 32 | } else { 33 | return false; 34 | } 35 | } 36 | 37 | /** 38 | * 使用Lua脚本，脚本中使用setnex+expire命令进行加锁操作 39 | * 40 | * @param jedis 41 | * @param key 42 | * @param UniqueId 43 | * @param seconds 44 | * @return 45 | */ 46 | public boolean Lock_with_lua(Jedis jedis,String key, String UniqueId, int seconds) { 47 | String lua_scripts = "if redis.call('setnx',KEYS[1],ARGV[1]) == 1 then" + 48 | "redis.call('expire',KEYS[1],ARGV[2]) return 1 else return 0 end"; 49 | List keys = new ArrayList<>(); 50 | List values = new ArrayList<>(); 51 | keys.add(key); 52 | values.add(UniqueId); 53 | values.add(String.valueOf(seconds)); 54 | Object result = jedis.eval(lua_scripts, keys, values); 55 | //判断是否成功 56 | return result.equals(1L); 57 | } 58 | 59 | /** 60 | * 在Redis的2.6.12及以后中,使用 set key value [NX] [EX] 命令 61 | * 62 | * @param key 63 | * @param value 64 | * @param timeout 65 | * @return 66 | */ 67 | public boolean lock(Jedis jedis,String key, String value, int timeout, TimeUnit timeUnit) { 68 | long seconds = timeUnit.toSeconds(timeout); 69 | return "OK".equals(jedis.set(key, value, "NX", "EX", seconds)); 70 | } 71 | 72 | /** 73 | * 自定义获取锁的超时时间 74 | * 75 | * @param jedis 76 | * @param key 77 | * @param value 78 | * @param timeout 79 | * @param waitTime 80 | * @param timeUnit 81 | * @return 82 | * @throws InterruptedException 83 | */ 84 | public boolean lock_with_waitTime(Jedis jedis,String key, String value, int timeout, long waitTime,TimeUnit timeUnit) throws InterruptedException { 85 | long seconds = timeUnit.toSeconds(timeout); 86 | while (waitTime >= 0) { 87 | String result = jedis.set(key, value, "nx", "ex", seconds); 88 | if ("OK".equals(result)) { 89 | return true; 90 | } 91 | waitTime -= sleepTime; 92 | Thread.sleep(sleepTime); 93 | } 94 | return false; 95 | } 96 | /** 97 | * 错误的解锁方法—直接删除key 98 | * 99 | * @param key 100 | */ 101 | public void unlock_with_del(Jedis jedis,String key) { 102 | jedis.del(key); 103 | } 104 | 105 | /** 106 | * 使用Lua脚本进行解锁操纵，解锁的时候验证value值 107 | * 108 | * @param jedis 109 | * @param key 110 | * @param value 111 | * @return 112 | */ 113 | public boolean unlock(Jedis jedis,String key,String value) { 114 | String luaScript = "if redis.call('get',KEYS[1]) == ARGV[1] then " + 115 | "return redis.call('del',KEYS[1]) else return 0 end"; 116 | return jedis.eval(luaScript, Collections.singletonList(key), Collections.singletonList(value)).equals(1L); 117 | } 118 | } 119 | -------------------------------------------------------------------------------- /src/main/java/com/redis/lock/utils/RedissonUtils.java: -------------------------------------------------------------------------------- 1 | package com.redis.lock.utils; 2 | 3 | import org.redisson.Redisson; 4 | import org.redisson.api.RLock; 5 | import org.redisson.api.RedissonClient; 6 | import org.redisson.config.Config; 7 | 8 | import java.util.concurrent.TimeUnit; 9 | 10 | /** 11 | * @description: 12 | * @author: pjmike 13 | * @create: 2019/04/24 00:39 14 | */ 15 | public class RedissonUtils { 16 | private static void trylock() { 17 | // 1. 配置文件 18 | Config config = new Config(); 19 | config.useSingleServer() 20 | .setAddress("redis://127.0.0.1:6379") 21 | .setPassword("123456") 22 | .setDatabase(0); 23 | //2. 构造RedissonClient 24 | RedissonClient redissonClient = Redisson.create(config); 25 | 26 | //3. 设置锁定资源名称 27 | RLock lock = redissonClient.getLock("redlock"); 28 | 29 | boolean isLock; 30 | try { 31 | isLock = lock.tryLock(500, 30000, TimeUnit.MILLISECONDS); 32 | if (isLock) { 33 | //TODO 成功获取到锁 执行业务逻辑 34 | System.out.println("获取到锁，执行相应的业务逻辑"); 35 | Thread.sleep(15000); 36 | } 37 | } catch (InterruptedException e) { 38 | //TODO 39 | } finally { 40 | //解锁操作 41 | lock.unlock(); 42 | } 43 | } 44 | 45 | public static void main(String[] args) { 46 | trylock(); 47 | System.exit(0); 48 | } 49 | 50 | public static void lock() { 51 | // 1. 配置文件 52 | Config config = new Config(); 53 | config.useSingleServer() 54 | .setAddress("redis://127.0.0.1:6379") 55 | .setPassword("123456") 56 | .setDatabase(0); 57 | //2. 构造RedissonClient 58 | RedissonClient redissonClient = Redisson.create(config); 59 | 60 | //3. 设置锁定资源名称 61 | RLock lock = redissonClient.getLock("redlock"); 62 | lock.lock(); 63 | try { 64 | System.out.println("获取锁成功，实现业务逻辑"); 65 | Thread.sleep(10000); 66 | } catch (InterruptedException e) { 67 | e.printStackTrace(); 68 | } finally { 69 | lock.unlock(); 70 | } 71 | 72 | } 73 | } 74 | -------------------------------------------------------------------------------- /src/main/resources/application.properties: -------------------------------------------------------------------------------- 1 | redis.config.host=39.106.63.214 2 | redis.config.port=6379 3 | redis.config.password= 4 | redis.config.max_idle=30 5 | redis.config.max_wait=15000 6 | redis.config.timeout=30000 7 | redis.config.retry_num=5 8 | 9 | 10 | 11 | 12 | 13 | -------------------------------------------------------------------------------- /src/test/java/com/redis/lock/LockApplicationTests.java: -------------------------------------------------------------------------------- 1 | package com.redis.lock; 2 | 3 | import org.junit.Test; 4 | import org.junit.runner.RunWith; 5 | import org.springframework.boot.test.context.SpringBootTest; 6 | import org.springframework.test.context.junit4.SpringRunner; 7 | 8 | @RunWith(SpringRunner.class) 9 | @SpringBootTest 10 | public class LockApplicationTests { 11 | 12 | @Test 13 | public void contextLoads() { 14 | } 15 | 16 | } 17 | -------------------------------------------------------------------------------- /src/test/java/com/redis/lock/RedisLockTest.java: -------------------------------------------------------------------------------- 1 | package com.redis.lock; 2 | 3 | import com.redis.lock.utils.RedisLockHelper; 4 | import org.junit.Before; 5 | import org.springframework.util.StopWatch; 6 | import redis.clients.jedis.Jedis; 7 | import redis.clients.jedis.JedisPool; 8 | import redis.clients.jedis.JedisPoolConfig; 9 | 10 | import java.util.concurrent.ExecutorService; 11 | import java.util.concurrent.Executors; 12 | import java.util.concurrent.TimeUnit; 13 | 14 | /** 15 | * @description: 16 | * @author: 13572 17 | * @create: 2019/04/24 22:54 18 | */ 19 | public class RedisLockTest { 20 | private ExecutorService executorService = Executors.newFixedThreadPool(200); 21 | private JedisPool jedisPool; 22 | private RedisLockTest() { 23 | JedisPoolConfig config = new JedisPoolConfig(); 24 | config.setMaxTotal(60); 25 | config.setMaxIdle(60); 26 | config.setTestOnReturn(true); 27 | config.setTestOnBorrow(true); 28 | String password = "123456"; 29 | jedisPool = new JedisPool(config, "39.106.63.214", 6379, 10000, password); 30 | } 31 | 32 | public static void main(String[] args) throws InterruptedException { 33 | RedisLockTest redisLockTest = new RedisLockTest(); 34 | RedisLockHelper redisLockHelper = new RedisLockHelper(); 35 | for (int i = 0; i < 200; i++) { 36 | redisLockTest.executorService.execute(()->{ 37 | try (Jedis jedis = redisLockTest.jedisPool.getResource()){ 38 | redisLockHelper.lock(jedis, "pjmike", "1", 20, TimeUnit.SECONDS); 39 | System.out.println("加锁成功"); 40 | redisLockHelper.unlock(jedis, "pjmike", "1"); 41 | } 42 | }); 43 | } 44 | redisLockTest.executorService.awaitTermination(1, TimeUnit.SECONDS); 45 | redisLockTest.executorService.shutdown(); 46 | } 47 | 48 | } 49 | --------------------------------------------------------------------------------